Residential fridge drains batteries to quickly

[browens62]

woodworker this may help

i copied this for my post a few months ago.

as you can see. we/you only have about 75 usable amp- half of total amps.
With that in mind the fig will not run very long.


battery information
i ran across this info

no wonder i screwed everytime i use the batteries

dealer installed 2 group 24


SOME COMMON BATTERY SIZE CODES USED ARE: (RATINGS ARE APPROXIMATE)

U1 34 to 40 Amp hours 12 volts
Group 24 70-85 Amp hours 12 volts
Group 27 85-105 Amp hours 12 volts
Group 31 95-125 Amp hours 12 volts
4-D 180-215 Amp hours 12 volts
8-D 225-255 Amp hours 12 volts
Golf Cart & T-105 180 to 225 Amp hours 6 volts
L-16, L16HC etc. 340 to 415 Amp hours 6 volts

[Rod Spohn]

Originally Posted by Charlie W

1, turn off your ice maker when you're towing or boondocking.
2, get rid of the 12 volt deep cycle batteries go to 4 6 volt batteries. "I use 4 Trojan t105 6v what the self-watering."
the two 12v batteries that came with my 3701LK would not last 4 hours with only the Samsung refrigerator.
If you will let one of your old batteries get below 11 volts it could have shorted out.

My 2 12v batteries don't last through the night even if I use the Generator to make sure they are at 100%. I'm going to do as you mentioned and change to 4 or maybe 6 6 Volt batteries. I also have 1 solar panel and want to add a second one soon. We boondock mostly and need more confidence in our electrical system.

[GreG L.]

Really good information here.

https://www.youtube.com/watch?v=PZ7HMRReZKY

[mazboy]

a typical 120 volt refrig pulls about: 'A 725-watt refrigerator draws 725/120 = 6 amps.'


something else is going on with your rig.

[Five O'clock Somewhere]

I have a Samsung residential and prior to installing addition batteries could only run about 4 – 5 hours before killing the battery. I installed 4 good quality 12-volt batteries and now can run an easy 24 hours without power and everything stays nice and cool and/or frozen as desired.

If you happen to be at the rally look me up and I will show you how I have them wired.

[Woodworker]

I wont be at the rally, but a pic will help
Are the 4 12v batteries wet or the agm type?

[66 Galaxie]

Originally Posted by mazboy

a typical 120 volt refrig pulls about: 'A 725-watt refrigerator draws 725/120 = 6 amps.'


something else is going on with your rig.

That's 6 amps AC. 725/12 = 60 amps DC.

[mhs4771]

I've posted before and will do again: We have a Whirlpool French Door fridge running off a Magnum 1000 watt Inverter. When the fridge is running it draws 11 amps from our batteries, which more or less matches the approx 1 amp draw on 120 VAC.

[glendodom]

Confused!!!

The reference link below contains a statement within noted:

“For example, let’s take a typical 100AH battery.
If your 12 Volt camping fridge is rated 5 Amp, it should take 20 hours to drain the
battery down to 10.5 volts, provided the battery is new and was fully charged.
5Amp load x 20Hours drain = 100AH required battery capacity.
In other words: 100AH capacity divided by 5Amp load = 20Hour running time.”

http://www.montanaowners.com/forums/...83#post1158483

I am running a single Coppertone 31M AGM battery which when traveling only supports a Samsung refrigerator which is noted as 3 amps. By the AGM battery chart it rated on the 20 hour draw for 5 amps at 1265 mins (21 Hrs). I normally on a long travel day make an average 6-7 hrs before being on shore power. Based on the data above one battery should normally suffice as long as it is a relatively new and fully charged battery, correct? No doubt 2 would be better for long term insurance but 1 seems to handle it for now.

[GreG L.]

I ran a test this week, replaced the two batteries that came with it with two Battle Born 100Ah lithium's (together they weighed the same as one of the old ones) charged them with shore power as well as cooling down the Samsung over night. The next day I took off the shore power around 8:00 pm and only ran the refrigerator over night, the next morning the lights were still on, on the refrigerator and was showing 13.?? volts. No I didn't measure the KW usage but I would be willing to bet it was close to 200, just before the batteries would shut down.
Not a real world test, I didn't run anything else, not even a light or open the refrigerator, just locked it up, and it was a cool night..

Two more batteries and another solar panel I think.